The porosity of intermediate packing factor is given by ______

• A. n = 1-[1/(6*(1-cosα)*( √(1-2cosα) )]
• B. n = (1-cosα)*( √(1+2cosα) )
• C. n = 1-[π/(6*(1-cosα)*(√(1-2cosα))]
• D. n = 6*(1-cosα)*(√(1-2cosα))